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51.
Tian Miao Xu Dehui Li Bing Wang Shuai Qi Miao Zhang Hao Liu Zhijie Liu Dingxin Chen Hailan Kong Michael G. 《Plasma Chemistry and Plasma Processing》2021,41(2):591-605
Plasma Chemistry and Plasma Processing - Cold atmospheric plasma (CAP) is a novel technology which is widely used in the biomedical field and has developed quickly over the past few years,... 相似文献
52.
PBO fiber is one of the most promising reinforcements in resin matrix composite because of its excellent mechanical properties. However, the inert and smooth surfaces make it the poor interface adhesion with resin matrix, which seriously limits the application in composites. In this article, we report a method to modify the surface of PBO fibers with 2,2-Bis (3-amino-4-hydroxyphenyl) hexafluoropropane(BisAPAF)in supercritical CO2 to enhance interfacial properties. Chemical structures, surface elemental composition and functional groups, and surface morphology were characterized by FT-IR spectrometer, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM), respectively. The mechanical properties of the samples were tested by a tensile tester. Static contact angle and microdebonding tests were used to characterize the wetting ability and interfacial shear strength (IFSS) of the fiber and epoxy resin. The results showed that the BisAPAF could be solved in scCO2 and introduced more groups, –NH2, –OH, and –CF3 on the fiber surface, resulting in the mechanical properties and the wettability of PBO fiber slightly improved. Moreover, the fiber surface roughness was also increased obviously. The IFSS between the modified PBO fiber and epoxy resin increased from 8.18 MPa to 31.4 MPa when the treating pressure was 14 MPa. In general, the method to modify PBO fibers surface using BisAPAF in scCO2 can effectively improve their interfacial properties. 相似文献
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Two new triterpene saponins, named hippophosides E and F ( 1 and 2 , resp.), together with two known compounds, were isolated from the seed residue of Hippophae rhamnoides L. Their structures were elucidated on the basis of chemical and spectral analysis, including 1D‐ and 2D‐NMR and HR‐MS experiments, and by comparison with literature data. 相似文献
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Effects of anodic oxidation on corrosion properties of Al coating by arc spraying in seawater 下载免费PDF全文
A layer of Al coatings was prepared on the S355 steel by arc spraying, which was conducted by anodic oxidation treatment; the morphologies, chemical element compositions and phases of Al coating, and anodic oxide layer were analyzed with field emission scanning electron microscope (FESEM), energy dispersive spectrometer (EDS) and X‐ray diffraction (XRD), respectively. The corrosion protections of Al coating before and after anodic oxidation were discussed with a seawater immersion test; the corrosion resistance mechanisms of Al coating and anodic oxide layer in the seawater were also investigated. The results show that the thickness of Al coating is about 300 µm by arc spraying, the sample surfaces become loose after seawater immersion corrosion and Cl? and O2? penetrate into the substrate from the cracks, destroying the binding properties of coating–substrate, and the coating fails. After anodic oxidation, the oxide layer is formed in the surface of Al coating with the thickness of about 30 µm; the corrosion products are mainly composed of Al(OH)3, which barraged the holes caused by seawater corrosion. The corrosion cracks are formed during the corrosion, while the number and depth of cracks decrease obviously after anodic oxidation treatment. The corrosion of Al coating becomes the local corrosion after anodic oxidation treatment, and the grains are smaller, which are easily nucleated to form a new corrosion resistance layer. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Interfacial bonding mechanism and bonding strength of AlTiCrN coating by cathodic arc ion plating 下载免费PDF全文
AlTiCrN coating was prepared on the surface of YT14 tungsten carbide cutting tools by cathodic arc ion plating with Ti, Al and Cr as targets. The surface morphologies, interface energy spectrum, phase and elements' binding energy of the coatings were observed with SEM, EDS, XRD and XPS, respectively, and bonding strength of the coating interface was measured with scratch tester. The results show that the phases of AlTiCrN coating are mainly composed of AlN, CrN and TiN, the crystal plane of (111) has a strong preferred orientation. The concentrations of Al, Ti, Cr, N in the coating are higher than those in the substrate, showing the gradient diffusion distribution at the bonding interface, while C atoms of the substrate have diffused into the lattices of TiN, AlN and CrN to form an obvious interdiffusion layer, and the average bonding strength of coating interface is 57.65 N. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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通过酰氯制备异硫氰酸酯,与5-(4-氨基苄基)-2,4-咪唑啉二酮反应合成了含2,4-咪唑啉二酮的N-苯甲酰基-N'-苯基硫脲,然后在三乙胺存在下再与溴丙酮发生碱催化缩合反应以中等以上收率合成了新型含2,4-咪唑啉二酮的4-甲基-3-苯基-2-酰亚胺噻唑啉,它们的化学结构经1H NMR,IR,HR-ESI-MS和化合物3g和4g的X-ray单晶衍射表征,硫脲与溴丙酮的反应机理通过化合物3g和4g的晶体结构得到进一步确证.初步生物活性测定结果表明:部分目标化合物对供试昆虫及菌种显现出良好的抑制活性,如在200 mg/L浓度下化合物3i和4q对小菜蛾的死亡率分别为86%和100%,在50 mg/L浓度下化合物4n对油菜菌核菌的抑制率为82.6%,而它们对油菜和稗草显示出微弱但并不特征的除草活性. 相似文献
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Yahui Zhang Lingwei Kong Jianbing Shi Bin Tong Junge Zhi Xiao Feng Yuping Dong 《中国化学》2015,33(7):701-704
A new type of AIE molecules based on hexaphenyl‐1,3‐butadienes was reported with respect to the synthesis and characterization. This material exhibited different maximum emission wavelength and enhanced emission intensity at different aggregate state (amorphous and crystalline state). 相似文献